Should I go to this party?

My boyfriend's mom and stepfather is going away for a whole week sometime this summer, I think around mid-June, and him and his step sister are going to throw a huge party while that are gone, I know how original. The party will involve alcohol, and me staying the night with my boyfriend (we have been dating almost three months and we haven't done anything, nor do I plan on doing anything with him.) I am tempted to go to the party, and it sounds really fin, but I also don't want to go at the same time. I am afraid that the party will get busted , and I really don't want to lose my parents trust, they are so lenient and trusting towards me already, and I also don't want to get drunk and do something I will regret. But, I could go and not drink, but like I said, the chances of getting caught and all that junk. What should I do? I need mature answers please. (: